Using apache mina for ssh using signed ssh-rsa-cert-01 from Certification Authority

There is an existing client configured and running (SshClient) using apache mina to ssh to one of our internal jump boxes. It currently uses PEM based authentication. Due to compliance we have to switch to using internally signed certificates (internally we are using hashicorp vault as a CA). I’m unable to find any documentation regarding how to use signed certificates for ssh in apache mina to start with. Is it not supported? Will I perhaps have to use any other java ssh library?